Variations in cord 25‐hydroxyvitamin D levels in Hispanic and Caucasian infants are not related to neonatal bone mineral status

Abstract

BackgroundAt birth, an infant's vitamin D status, as assessed by 25‐hydroxyvitamin D level (25‐OHD) is dependent on the 25‐OHD status of the mother. There are few data regarding 25‐OHD in Hispanic infants and the relationship between 25‐OHD and bone mineral outcomes.ObjectivesTo evaluate the range of 25‐OHD in Hispanic newborn infants (HNI) compared to Caucasian newborn infants (CNI) in a southern US setting and to determine if cord blood 25‐OHD is related to bone mineral status in the first week of life.MethodsAt birth, umbilical cord blood was analyzed using the Diasorin RIA (Diasorin Inc, Stillwater, MN) for 25‐OHD. Approximately 1 week after birth, infants' received a whole body dual‐energy x‐ray absorptiometry measurement to assess bone mineral content/density (BMC/BMD).ResultsData are Mean ± SD. The 25‐OHD levels were significantly lower in HNI (n=20) versus CNI (n=18) (17.2 ± 5.7 ng/mL vs 24.1 ± 6.8 ng/mL, p = 0.002). There was no difference in whole body BMC or BMD between HNI and CNI (BMD: 0.197 ±0.013 g/cm2 vs 0.196 ± 0.011 g/cm2, p = 0.9). Using a value of 20 ng/mL to indicate possible vitamin D insufficiency there was no difference in BMC or BMD of 19 infants with 25‐OHD levels < 20 ng/mL vs 19 infants with 25‐OHD levels ≥ 20 ng/mL (BMD: 0.195 ± 0.015 g/cm2 vs 0.197 ± 0.011 g/cm2, p = 0.8).ConclusionHispanic newborns in a southern US setting have lower 25‐OHD than Caucasians but this is not related to newborn bone mineral status.Supported in part by the Marshall Klaus Award of the American Academy of Pediatrics